Bostick, the 6-foot-3, 250 pound tight end spent the last three years with the Green Bay Packers after he played 24 games for the Packers the past two seasons. He had nine receptions for 123 yards in two seasons on the active roster before being waved in February. The Minnesota Vikings claimed him for training camp, but released him on Aug. 30.

McFadden played seven games with the San Francisco 49ers last season and collected five tackles after he joined the the team in November. The 5-foot-10, 190 pound corner back was drafted in the third round by the Cleveland Browns in 2013 where he played 16 games as a rookie with 16 tackles.

Nelson returns to the Valley after playing college football for Arizona State where he had 73 tackles and nine interceptions in two seasons with the Sun Devils. The 5-foot-9, 175 pound corner back signed with the Browns in 2014 and played seven games.

Okoye is a former British Olympian who competed in the 2012 London Summer Olympics and is a record holder in the discus. Prior to spending last season on the 49ers practice squad, the 6-foot-6, 304 pound Okoye is a former rugby player with no prior football experience before signing with San Francisco.